Answer:
The return of blood to the heart is assisted by the action of the skeletal- muscle pump. As muscles move, they squeeze the veins running through them. Veins contain a series of one-way valves, and they are squeezed, blood is pushed through the valves, which then close to prevent backflow.
Answer:
um go on the other brianly
Explanation:
Answer:
there is a good and bad effect on the world, the positive reason being economically. smoking is a great money maker it was worth US$88 billion dollars in 2018. the negative reason is the pollution and what it does to the human body such as cancer
Explanation:
The process of RNA formation from DNA is transcription.
Restriction endonuclease is the answer
